Brush holder and tension device



. April 21, 1942-l H. wElsslNGE-R l2,280,735

BRUSH HOLDER AND TENSION DEVICE]I Filed sept. 23, @4l 2 sheets-sgaet l lmmmunm 6 1 v J y g I'.

Izzi/effin?!- April 2l, 1942. H, wx-:lsslNGER BRUSH HOLDER AND TENSION DEVICE 'Filed Sept. 23, 1941 2 Sheets-Sheet 2 Patented Apr. 21, 1942 UNITED STATESPATENT OFFICE BRUSH HOLDER TENSION DEVICE Harry Weissnger, Philadelphia, Pa.

Application September 23, 1941, Serial No. 412,045

(rc1. 1v1-324) 11 Claims.

This invention relates to new and useful improvements in electric brush holders and more particularly to holders embodying mechanism for tensioning or urging the brush or brushes into Contact with the commutator of a motor, genf erator or the like.

Holders embodying tensioning devices for the brushes of electric motors and generators as heretofore made embody tensioning arms or levers which are pivoted to the holder with the result that the tension exerted by such levers or arms upon a brush is angular with respect to the brush and not in a direction longitudinally of the brush. Furthermore, these pivoted lever types of brush tension devices are limited to use with brushes of relatively short length due to the fact that it is possible only for the levers to engage the upper ends of such brushes through a limited portion of the circumference of their pivotal movement.

With the foregoing observations in mind, the principal object of the present invention is to provide a novel brush holder and tensioning device wherein the tension is exerted upon the brush longitudinally in the plane thereof and in the direction of its contact with the motor or generator slip-ring or commutator.

Another object of the invention is to provide a brush holder and tensioning device of the character set forth which is constructed and arranged to permit of the easy and quick removal and replacement of brushes and which is capable of use with brushes of substantial length.

Another object of the invention is to provide a novel brush holder and tensioning device of the .i

ticular position or positions to which the tensioning means may be adjusted.

A- further object of the invention is to provide a novel brush holder and tensioning means of the character described which is of relatively simple, rugged construction, and entirely foolproof in use and operation.

These and other objects of the invention and the various features and details of the constructionand operation thereof are hereinafter fully set forth and shown in the accompanying drawings, inwhich:

Figure 1 1s a View in. perspective of a double brush. holder and tensioning means embodying the present invention.

Figure 2 is a view in section taken on line 2-2, Figure l.

Figure 3 is a View in section taken on line 3 3, Figure 1.

Figure 4 is a view in perspective of a modified construction whereby the tensioning means may be connected to and exert pressure upon a brush; and

Figure 5 is a View in perspective of a single brush holder and tensioning means made according to the inventon.

1 Referring now to the drawings, and particularly Figures 1 to 3 thereof, reference numerals I, I designate a pair of electric motor or generator brushes mounted side by side in a brush box 2 and arranged to reciprocate or slide Vertically therein independently of each other, the said brushes I, I being independently urged downwardly toward the rotary Contact surface of a motor or generator by means of blocks 3, 3 which engage upon the upper ends of said brushes and are tensioned downwardly longitudinally in the plane of the brushes as indicated by the arrows (see Figure 2).

The aforesaid brush box 2 forms or comprises the central part of a holder structure H which is formed to provide at opposite sides of said brush box 2 housing portions 4, 4 for the brush tensioning mechanisms, and projecting upwardly from the outer end of one of said housing portions 4 is a bracket or supporting portion 5 having a stud (not shown) extending upwardly therefrom to receive thereon a supporting member 6. As shown in Figure 1, the central brush box 2 is of greater Width and height than the adjacent housing portions 4 and the latter are in open communication with said brush box through openings 8 which are the full width of said housings and extend entirely to the bottom thereof.

The opposite side wall portions 4a, 4b of each housing 4 are provided with suitable axially aligned bores 9 and Ii) respectively, and in these bores of each housing 4 is mounted a shaft II arranged, as indicated, to extend transversely across said housings 4, 4. One end of each of the shafts I I is of reduced diameter as indicated at I2 and this end projects outwardly through the bore 9 in the housing wall portion 4a and has a cotter pin I3 passed and secured through its projecting end portion. The reduced diameter i2 of the one end portion of each shaft II provides a shoulder I4 which is adapted to abut against the interior surface of the wall portion 4a which thereby acts as a stop against lateral displacement of said shafts in that direction.

The other end of each shaft II is journalled in an adjusting element or wheel I5 and the latter in turn is provided with an outwardly projecting smaller hub portion I6 which is journalled in the bore I0 of the wall portion 4b of each housing 4 as best shown in Figure 3 of the drawings. This wall portion 4b of each housing is split or severed to the bore III as indicated at Il so that the hub portion I6 of each adjusting wheel may be rigidly clamped in any desired rotary position with respect to its Wall portion lib by means of a screw or like element I8. The adjusting element I has in its peripheral surface a series of sockets or recesses It forreceiving a nail or other instrument to turn or rotate said element i5 as desired.

Rotatably mounted upon each shaft II between the wall portion 4a and the inner end face of the adjusting element i5, which is journalled in the opposite housing wall portion 4b as aforesaid, isa roller member 2B. As shown in Figure 3 of the drawings, each of these roller members 2li comprises a central hub sleeve portion 2| and an outer cylindrical portion 22 spaced concentrically with respect to said hub sleeve portion 2i thereby to provide an intermediate `annular recess 23 lengthwise of said members 2l] inwardly thereof from the end faces of the members 2t which are disposed adjacent the adjusting elements I5. These roller members extend substantially entirely between the housing wall portions 4a and the adjusting element I5 and thus maintain the latter properly positioned 'with their hub portions journalled in the bores Ill in the opposite housing wall portions 4b.

A coiled spring 2d is disposed within the recess 23 of each roller member 2t, as shown in Figure 3, and the opposite end portions of the springs 24 are inserted in or engage suitable openings 2b and 25 formed respectively in the adjusting elements I5 and the end portion of said roller members 2@ disposed adjacent the housing wall portions llc, said springs 24 being coiled and connected to said parts so that the roller members 20 are urged thereby, respectively, in the direction indicated by the arrows in Figure 2 of the drawings.

Suitably secured to the exterior surface of each roller member 2li by screws, rivets or the like 21, is one end of a tape or tape-like element 28 and an adjacent portion oi the length of each such tape element 28 passes circumferentially its roller 2t in a direction opposite to that in which the said rollers are urged or tensioned by their springs 24. From the inner side oi the rollers t!) the tape elements 2S pass downwardly, then about an idler roller 29 suitably journalled in the lower portion of each housing 4 adjacent the brush box 2, and then upwardly from said idler rollers 29 where the other end portion of each oi said tape elements is suitably secured to its corresponding brush contact block 3 previously described (see Figure 2).

As previously stated, the tape elements 28 extend about their rollers 2D in a direction opposite to the direction in which said rollers 20 are urged by their springs 2li, and hence said springs 24 operate continuously to tend to cause the said tape elements to wind-up upon their rollers 2i). Thus there is a constant pull exerted on said tape elements 23 which in turn exert a downward pull upon the brush contact blocks 3, 3 with the result that the brushes i, I likewise are urged in a downward direction within the brush box 2, and, from the previous description, it will be seen that the tension of the springs 24, and consequently the downward thrust applied to the brushes I, I, may be adjusted to exactly the desired magnitude by rotation of the adjusting elements I5 about the shafts II. It will be understood, of course, that prior to adjustment of element I5 as aforesaid, the screw I8 must rst be loosened to reduce or release the brake action of the split portions I'I of walls b upon the hubs It, and,

then, after adjustment of the elements I5, the screws I8 must be tightened in order to securely clamp the said elements I5 in the position to which adjusted.

The brush Contact blocks 3, 3 may extend substantially the full width of the brush box 2, and, of course, must extend at least beyond the width of the openings 8 which provide communication between said box E and the housing portions 4. As previously pointed out, these blocks 3, 3 are not connected to the brushes I, I but merely engage upon their upper end faces in the manner or relation shown in Figure 2 of the drawings. Thus the blocks 3, 3 are removable frorn the brush box 2, and for this purpose the adjacent end portions of the tape elements 28 are suitably formed to provide upwardly projecting tabs or handle portions 28a. Consequently, all that it is necessary to do in order to remove either or both brushes I, I, is to grasp the tab or tabs Eta and then pull upwardly thereon against the tension oi springs 24 until the blocks 3, 3 clear the top edge of the brush box 2, after which they may be permitted to engage upon the upper edge oi the walls of the housing portions. The brushes may then be removed and replaced with new brushes after which the blocks 3, 3 are reinserted downwardly into the brush box 2 and engaged upon the upper ends of the respective brushes, the tension of the springs 24 operating as before to urge the new brushes downwardly with an even uniform thrust into Contact with the rotating element oi' the motor or generator.

t will be noted, particularly in Figure 2 of the drawings, that the construction and arrangement of the device of the present invention is such that the thrust or tension exerted upon the brushes l, I is substantially vertically downward in the plane of said brushes with the result that the contact ends oi' the brushes will Wear evenly and as said brushes wear down upon continued use they will be maintained evenly in oontact with the rotating part under uniform, constant pressure by means ci' the tensioning mechanisms described above.

With respect to the electrical details of the present invention, it is pointed out that connections to the brushes I, l may be eiected in numerous ways, and, in the drawings, suitable conductors 36 are led down past the ends of the brush contact blocks 3, and are suitably connected to the brushes I, I.

In Figure fi oi' the drawings there is shown a. modified construction of brush and thrust block, wherein the brush Ia has its upper end face provided with suitably located sockets 3I arranged to receive pins 32 which depend from the underside of the brush Contact thrust block 3a, the tape element 2t being secured to and acting upon said block 3a in the manner previously described in connection with the blocks 3. By this construction andv arrangement relative iixation of the blocks with respect to the brushes is obtained.

In Figure 5 of the drawings there is shown a slightly modified form of device from that previously described herein and embodying only a, single brush I and associated tension mechanisin. However, apart from this difference, the construction and operation of this form of the device is similar to that hereinabove described, and like reference numerals have been applied to parts of this form of device which are the same fas like numbered parts of the dual form of device rthe brush box and offset from the roller memillustrated in Figures 1 to 4 of the drawings.

From the foregoing it will be observed that the present invention provides a device of the type set forth wherein the tension is exerted upon the brush or brushes longitudinally in the plane thereof, and wherein the construction and arrangement permits of the ready and easy removal and replacement of brushes without the necessity for detaching from the device any part or parts of the tensioning mechanism. Too, the device of the invention is simple and fool-proof, and the tension may be adjusted to the exact degree desired without restriction to any certain fixed adjustments because of any limitation in theparticular positions to which the tensioning means may be adjusted.

While certain particular embodiments of the invention have been herein illustrated and described, it is not intended that the invention be limited to this disclosure but that changes and `modications may be made therein and thereto within the scope of the annexed claims.

I claim:

i. A brush holder comprising a frame structurey including a brush box and a housing disposed at least at one side of said brush box, a shaft supported by said housing, a roller member rotatably mounted on said shaft, an idler roll rotatably supported by the housing adjacent the brush box and offset from the roller member in the direction of thrust to be exerted upon a brush positioned in the brush box, a pressure block slidable within said brush box and arranged to engage upon the end face of such r brush, an elongated flexible element having its opposite ends connected respectively to said pressure block and the roller member with its intermediate portion passing about said idler roll, and spring means constructed and arranged to 1 urge said roller. member in a predetermined direction of rotationtending to wind the elongated iiexible element thereon and thereby exert a pull on the latter urging the said pressure block against the brushin the brush box.

, 2. A brush holder comprising a frame struc- .ture including a brush box and a housing disposed at least at one side of said brush box, a. shaft supported by said housing, a roller member rotatably mounted on said shaft, an idler roll rotatably supported by the housing adjacent the brush box and oiset from the roller member in the direction of thrust to be exert-ed upon a brush positioned in the brush box, a pressure block slidable within said brush box and arranged to engage upon the end face of such brush, an elongated flexible element having its opposite ends connected respectively to said pressure block and the roller member with its intermediate portion passing about said idler roll, spring means constructed and arranged to urge said roller member in a predetermined direction of rotation tending to wind the elongated flexible element thereon and thereby exert a pull on the latter urging the said pressure block against the brush in the brush box, and means operable at will for Varying and regulating the force 0i said spring means and consequently the pressure exerted by the block upon the brush.

3. A brush holder comprising a frame structure including a brush box and a housing disposed at least at one side of said brush box, a shaft supported by said housing, a roller member rotatably mounted on said shaft, an idler roll rotatably supported by the housing adjacent ber in the direction of thrust to be exerted upon a brush positioned in the brush box, a pressure block slidable within said brush box and arranged to engage upon the end face of such brush, an elongated flexible element having its opposite ends connected respectively to said pressure block and the roller member with its intermediate portion passing about said idler roll, an adjusting element rotatable on the shaft, and spring means connected between said adjusting element and roller member constructed and arranged to urge said roller member in a predetermined direction of rotation tending to wind the elongated iiexible element thereon and thereby exert a pull on the latter urging the said pressure block against the brush in the brush box, the adjusting element being adjustable at will to regulate the force of the spring means and consequently the pressure exerted by the block upon the brush.

4. A brush holder comprising a frame structure including a brush box and a housing disposed at least at one side of said brush box, a shaft supported by said housing, a roller member rotatably mounted on said shaft, an idler roll rotatably supported by the housing adjacent the brush box and offset from the roller member in the direction of thrust to be exerted upon a brush positioned in the brush box, a pressure block slidable within said brush box and arranged to engage upon the end face of such brush, an elongated exibie element having its opposite ends connected respectively to said pressure block and the roller member' with its intermediate portion passing about said idler roll, an adjusting element rotatable on the shaft, spring means connected between said adjusting element and roller member constructed and arranged to urge said roller member in a predetermined direction of rotation tending to Wind the elongated flexible element thereon and thereby exert a pull on the latter urging the said pressure block against the brush in the brush box, the adjusting element beinT adjustable at will to regulate the force of the spring means and consequently the pressure exerted by the block upon the brush, and means for securing the said adjusting element in any position to which adjusted.

5. A brush holder comprising a frame structure including a brush box and a housing disposed at least at one side of said brush box, a shaft supported by said housing, an adjusting element mounted on said shaft for rotation, a roller member mounted on said shaft for rotation adjacent said adjusting element, said roller member having an annular recess extending longitudinally therein inwardly from the end face of the roller member adjacent said adjusting element, an idler roll rotatably supported by said housing adjacent the brush box and offset from said roller member in the direction of thrust to be exerted upon a brush positioned in the brush box, a pressure block slidable Within said brush box and arranged to engage upon the end face of such brush, an elongated iiexible element having its opposite ends connected respectively to said block and the roller member With its intermediate portion passing about said idler roll, and spring means disposed in the annular recess of the roller member and having its opposite ends connected respectively to said roller member and the adjusting element so that said spring tends to urge the roller member in a direction of rotation tending to wind the elongated flexible element thereon and thereby exert a pull on the latter urging the said pressure block against the brush in the brush box, the adjusting element being adjustable at Will to regulate the force of the spring and consequently the pressure exerted by the block against the brush.

6. A brush holder comprising a frame structure including a brush box and a housing disposed at least at one side of said brush box, a shaft supported by said housing, an adjusting element mounted on said shaft for rotation, a roller member mounted on said shaft for rotation adjacent said adjusting element, said roller member having an annular recess extending longitudinally therein inwardly from the end face of the roller member adjacent said adjusting element, an idler roll rotatably supported by said housing adjacent the brush box and olset from said roller member in the direction of thrust to be exerted upon a brush positioned in the brush box, a pressure block slidable within said brush box and arranged to engage upon the end face of such brush, an elongated iiexible element having its opposite ends connected respectively to said block and the roller member with its intermediate portion passing about said idler roll, spring means disposed in the annular recess of the roller member and having its opposite ends connected respectively to said roller member and the adjusting element so that said spring tends to urge the roller member in a direction of rotation tending to wind the elongated exible element thereon and thereby exert a pull on the latter urging the said pressure block against the brush in the brush box, the adjusting element being adjustable at will to regulate the force of the spring and consequently the pressure exerted by the block against the brush, and means for securing the adjusting element in any position to which adjusted.

7. A brush holder comprising a frame structure including a brush box and a housing disposed at least at one side of said brush box, said housing having spaced side wall portions provided with axially aligned bores therein, a shaft extending through said bores in the housing walls, an adjusting element mounted on said shaft for rotation and disposed inwardly adjacent one of said housing wall portions, said adjusting element having a projecting hub portion journalled in the bore of said one housing wall portion, a roller member mounted on said shaft for rotation and extending therealong between the adjusting element and the other Wall portion of said housing, said roller member having an annular recess extending longitudinally therein inwardly from the end face of the roller member adjacent said adjusting element, an idler roll rotatably supported by said housing adjacent the brush box and offset from said roller member in the direction of thrust to be exerted upon a brush positioned in the brush box, a pressure block slidable within said brush box and arranged to engage upcn the end face of such brush, an elongated iiexible element having its opposite ends connected respectively to said block and the roller member with its intermediate -portion passing about said idler roll, and spring means disposed in the annular recess of the roller member and having its opposite ends connected respectively to said roller member and the adjusting element so that said spring tends to urge the roller member in a direction of rotation tending to wind the elongated flexible element thereon and thereby exert a pull on the latter urging the said pressure block against the brush in the brush box, the adjusting element being adjustable at will to regulate the force of the spring and consequently the pressure exerted by the block against the brush.

8. A brush holder comprising a frame structure including a brush box and a housing disposed at least at one side of said brush box, said housing having spaced side wall portions provided with axially aligned bores therein, a shaft extending through said bores in the housing walls, an adjusting element mounted on said shaft for rotation and disposed inwardly adjacent one of said housing wall portions, said adjusting element having a projecting hub portion journalled in the bore of said one housing wall portion, a roller member mounted on said shaft for rotation and extending therealong between the adjusting element and the other wall portion of said housing, said roller member having an annular recess extending longitudinally therein inwardly from the end face of the roller member adjacent said adjusting element, an idler roll rotatably supported by said housing adjacent the brush box and 01T- set from said roller member in the direction of thrust to be exerted upon a brush positioned in the brush box, a pressure block slidable within said brush box and arranged to engage upon the end face of such brush, an elongated iiexiole element having its opposite ends connected respectively to said block and the roller member with its intermediate portion passing about said idler roll, and spring means disposed in the annular recess of the roller member and having its opposite ends connected respectively to said roller member and the adjusting element so that said spring tends to urge the roller member in a direction of rotation tending to wind the elongated flexible element thereon and thereby exert a pull on the latter urging the said pressure block against the brush in the brush box, the adjusting element being adjustable at will to regulate the force of the spring and consequently the pressure exerted by the block against the brush, and means for securing the adjusting element in any position to which adjusted.

9. A device as claimed in claim l wherein the pressure block is provided with a plurality of pin elements projecting from its brush Contact face and arranged for engagement with correspondingly positioned sockets in the end face of a brush positioned in the brush box.

l0. A device as claimed in claim 5 wherein the pressure block is provided with a plurality of pin elements projecting from its brush contact face and arranged for engagement with correspondingly positioned sockets in the end face of a brush positioned in the brush box.

11. A device as claimed in claim 7 wherein the pressure block is provided with a plurality of pin elements projecting from its brush Contact face and arranged for engagement with correspondingly positioned sockets in the end face 0I a brush positioned in the brush box.

HARRY WEISSINGER. 

